The present invention relates to printing machines, and more particularly to automatic inking systems for cassette tape cartridge direct ink printing machines.
In the past, printing on cassette tape cartridges was generally accomplished by preprinting labels and affixing the labels to the cassettes. Printing directly onto cassettes was generally avoided because of the difficulties involved. Cassette cases are generally made of a thin plastic which tends to bend when a fixed pressure, such as from a print head, is applied. Furthermore, one side of a cassette is open for access to the enclosed tape by a tape player. The cassette opening case depth is increased to accommodate this opening thereby presenting a printing surface which is not flat. The effect of these two structural attributes of cassettes was that printing directly onto cassette generally resulted in a distorted, smudged and/or unfocused print image.
In more recent times, several machines were developed to print directly onto cassettes. The machines developed generally used offset printing processes and/or tapes. Offset printing onto cassettes requires many moving parts and results in complex and costly printing machines.
To overcome these problems applicant developed a cassette tape cartridge direct ink printing machine, for which U.S. Pat. No. 5,121,687 was issued on Jun. 16, 1992. Said patent ('687) is incorporated herein by reference. The '687 machine combined a vertical cassette cartridge feed mechanism with a unique inking system and direct printing process. Ink rather than tapes was used. The complexity and expense of offset printing and tapes was thereby eliminated.
Application of ink to the '687 machine is done by manually applying a paste ink to the '687 ductor roller 113. One ink application generally lasts for 300 cassettes, with 5 lines of print each. Because of the success of the '687 machine in continuously printing cassettes, the need to interrupt operation to apply the ink paste is inefficient.